Tremolo picking

How about that, I mean that ultra-fast picking of one string...is there a special way to hold the pick, with three fingers inside the palm or outside, and how to strum the string, with the wrist or with the forearm? Any good practice methods for that? And what is the best pick thickness?

there is no single best way to do it. experiment and find the way that suits you best or, better, work on them all. for me, personally, I have found that a slight twist to the pick so that it attacks the string at an angle and more wrist motion rather than elbow is best...but that's just me. You watch 10 great guitarists and you'll see 10 diff variations and they each get the job done

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